REM meter for pulsed sources of neutrons

Technical Report · Wed Aug 13 04:00:00 EDT 1980

DOI:https://doi.org/10.2172/7023018· OSTI ID:7023018

Thorngate, J E; Hunt, G F; Rueppel, D W

A rem meter was constructed specifically for measuring neutrons produced by fusion experiments for which the source pulses last 10 ms or longer. The detector is a /sup 6/Li glass scintillator, 25.4 mm in diameter and 3.2 mm thick, surrounded by 11.5 cm of polyethylene. This detector has a sensitivity of 8.5 x 10/sup 4/ counts/mrem. The signals from this fast scintillator are shaped using a shorted delay line to produce pulses that are only 10 ns long so that dose equivalent rates up to 12 mrem/s can be measured with less than a 1% counting loss. The associated electronic circuits store detector counts only when the count rate exceeds a preset level. When the count rate returns to background, a conversion from counts to dose equivalent is made and the results are displayed. As a means of recording the number of source pulses that have occurred, a second display shows how many times the preset count rate has been exceeded. Accumulation of detector counts and readouts can also be controlled manually. The unit will display the integrated dose equilavent up to 200 mrem in 0.01 mrem steps. A pulse-height discriminator rejects gamma-ray interactions below 1 MeV, and the detector size limits the response above that energy. The instrument can be operated from an ac line or will run on rechargeable batteries for up to 12 hours.

• Research Organization: California Univ., Livermore (USA). Lawrence Livermore Lab.
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 7023018
• Report Number(s): UCID-18792
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700102* -- Fusion Energy-- Plasma Research-- Diagnostics
DESIGN
DETECTION
LI-DRIFTED DETECTORS
MAGNETIC MIRRORS
MEASURING INSTRUMENTS
MFTF DEVICES
NEUTRON DETECTION
OPEN PLASMA DEVICES
RADIATION DETECTION
RADIATION DETECTORS
SCINTILLATION COUNTERS
SEMICONDUCTOR DETECTORS
SENSITIVITY
THERMONUCLEAR DEVICES